most sport (reclinable or multi position) and racing seats are universal and can be put in anything. you just need to get focus specific brackets to mount them on. I had a set of megan racing sport seats in my 03 and they were pretty comfy overall. only thing I didn't like was there wasn't a lot of lower back support in them as with most inexpensive seats. some seat makers offer a lumbar add on option that's basically an air pillow put in the seat. would be worth looking into getting that if you do a lot of driving. Been a while, but if i remember correctly I got the weapon r brackets for mine and were about $80 for the pair. they come with some pre drilled holes, but I did have to drill a couple new holes to bolt them up correctly.
you can always get better seats out of a different car as well. the 08-11 focus seats will bolt in just fine and are more comfortable. or get seats from whatever and a bracket and install. a guy out here got some from a rx8 and he said it wasn't a bad install to put them in.
2010 Volvo C70
2011 Harley FLHTK
Midwest Crew #22